That's a current - or recent - BC Rich Mockingbird copy that was made in China, I suspect, and has very little to do with the Japanese or Korean made guitars of the 80s and early 90's.

I can't find them currently listed on eBay Germany, but they were marketed through a German firm; they are generally supposed not to have had the quality we've experienced with Matsumoku made guitars....

_________________FWIW, an after market esoteric nut is a solution to a problem that doesn't exist, and a great way to convert your money into someone else’s.